Agronomic and economic efficiency of the complex application of mineral fertilizers and Mizorin biologics on alfalfa crops of the Aislu variety in the soil and climatic conditions of the Republic of Tatarstan

Field experiments on alfalfa crops of the Aisylu variety were conducted in 2020-2022 on the basis of the Agrobiotechnopark of the Kazan State Agrarian University (Narmonka village of the Laishevsky municipal district of the Republic of Tatarstan). The soils of the experimental site are gray forest with the following agrochemical indicators: the content of humus according to Tyurin is 3.0%, mobile phosphorus is very high (> 250 mg/kg) and exchangeable potassium is increased (145 mg/kg according to Kirsanov). The reaction of the soil medium was close to neutral (pH 6.6). The aim of the research was to develop methods to increase the yield and quality of the green mass of alfalfa on the basis of the use of various types of mineral fertilizers and the biological preparation Mizorin. The scheme of the experiment included the following options: control (without fertilizers and biologics); root dressing in spring and after the first mowing with ammonium nitrate of 100 kg/ha; root dressing in spring and after the first mowing with nitrogen strip of 100 kg/ha; root dressing in spring and after the first mowing with ammonium nitrate of 100 kg/ha in combination with leaf dressing with the biopreparation Mizorin 2 l/ha; root dressing in spring and after the first mowing with a 100 kg/ha nitrogen strip in combination with a leaf dressing with the biopreparation Mizorin 2 l/ha. Early spring feeding of alfalfa and after the first mowing with ammonium nitrate at the rate of 100 kg / ha provided additional 4.7 t/ha of green mass. In the variant of azofoska top dressing, the yield increase increases to 29.8 t/ha of the green mass of the research object. The maximum yield of the studied crop was obtained in variants of combining root and leaf fertilization, the increase in green mass increased to 64.4 and 92%, respectively.